hi,

thanks you Kai, now I see what did confuse me. It is here:

The BC337 of all other rows are turned-on, and by this, shunting the current flowing through according 240Ohm resistors directly to ground.

You see, my Teacher was always saying me: "do the both schematic and logic so that there should not be a current at passive state of device".

In your schematic it is 5.2mA x8. When I have first looked at it I thought: "why are all row transistors opened when nothing happens??"

Regards,
Oleg